Gaseous electric discharge device



Aug. 28, 1934. K. WXEGAND GASEOUS ELECTRIC DISCHARGE DEVICE Filed April 24. 1931 ATTORN'EY Patented Aug. 28, 1934 UNITED STATES PATENT OFFICE Kurt Wiegand, Berlin, Germany, assignor to General Electric Company, a corporation of New York Application April 24, 1931, Serial No. 532,567 In Germany July 7, 1930 5 Claims.

The present invention relates to gaseous electric discharge devices generally and more particularly the invention relates to such devices in which the positive column is surrounded by a tube of transparent refractory material in the glass container of the device said tube having a different coeflicient of expansion than said container.

Hitherto, it has been the practice in the art to fuse the tube to the container, in which case a step-seal had to be used between the tube and the container in order to make an hermetically tight container owing to the difierent coeflicients of expansion of these members. The object of the present invention is to provide a tube of transparent refractory material, such as quartz, in the glass container of a gaseous electric discharge device, said tube having a different coeflicient of expansion than said container, without the necessity of providing a step-seal between said container and said tube.

In accordance with this object the invention comprises a quartz tube having its ends inserted into tubular extensions of the soft glass electrode chambers of the gaseous electric discharge device and being maintained in position by means of a ground or fitted joint between the outer walls of its ends and the inner walls of the tubular parts of the electrode chambers. Said joint is fine enough to prevent the passage of the gaseous discharge therethrough so that it does not develop outside the quartz tube, but said joint is pervious to the gaseous filling so that the gaseous filling in the quartz guide tube is the same in pressure and character as that in the soft glass container of the device.

In the drawing accompanying and forming part of this specification'three embodiments of the invention are known for purposes of disclosure, in which,

Fig. 1 is a side elevational view of one embodiment of the invention,

Fig. 2 is a side elevational view of another embodiment of the invention,

Fig. 3 is a side elevational view of still another embodiment of the invention, and

Fig. 4 is a sectional view along the line 44 of Fig. 3.

Like numbers denote like parts in all views of the device.

Referring to Fig. 1 the invention comprises a tube 1 of a transparent refractory material such as quartz, or hard glass shaped in the form of a helix as shown, said tube 1 serves as a guide for the positive column discharge. The ends of said tube 1 are inserted into the soft glass electrode chambers 3 which are so shaped that a tubular portion of each electrode chamber 3 surrounds and extends along the end of the quartz tube 1 inserted therein. The ends of said tube 1 and the inner walls of the tubular part of the electrode chambers 3 are ground or fitted so that the joint is fine enough to prevent the movement of tube 1 in ball-shaped container 5 and to prevent the development of the gaseous discharge outside the tube; it is not an hermetic joint however so that the gaseous content of tube 1 is at the same pressure and is of the same character as that in container 5. The electrode-chambers 3 are fused to the ends 4 of said container 5 and contain the filamentary heated electrodes 2.

The embodiment of the invention shown in Fig. 2 is the same in principle as that shown in Fig. 1, but the device shown in Fig. 2 is more compact than that shown in Fig. 1 as the stem parts 4 of the container 5 are arranged in parallel planes and are close to each other.

In the embodiment of the invention shown in Fig. 3 the quartz tube 1 and the soft glass container 5 are straight tubes as shown. The joint 30 between the electrode chambers 3 and the ends of quartz tube 1 is of the same character as that described in conjunction with Fig. 1. In this embodiment of the invention the electrode chambers 3 are not fused to the container 5, but are 35 supported by a metal ring 6 encircling them, said ring 6 has spring parts 7 pressing outwardly against the inner walls of container 5 as shown in Fig. 4. Current leads 8 for the electrodes 2 are sealed into stems 9 of container 5 as shown in Fig. 3. This construction is notas rigid as the devices disclosed in Figs. 1 and 2 and may be used in places where vibration is present.

While I have shown and described particular embodiments of my invention it will be understood of course that various substitutions, modifications and changes in the form and details of the device and in its use and operation may be made by those skilled in the art without departure from the broad spirit and scope of the invention, for example, other suitable electrodes may be used and, if desired, the ends of quartz or'hard glass tube 1 may be slipped over the ends of the electrode chambers 3, the gaseous filling maybe of any of the conducting gases or mixtures thereof well known in the art.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. An electric discharge device comprising a container having stems, electrodes sealed therein, llO

a gaseous atmosphere therein, a tube of transparent, refractory material surrounding the electric discharge path between said electrodes and open-ended chambers for said electrodes, said tube having a different coeiilcient of expansion than said container, said chambers having the same coefficient of expansion as said container and enclosing the stems of said container, the adjacent ends of said tube and said chambers being concentric and overlapping.

2. An electric discharge device comprising a container having stems, electrodes sealed therein, a gaseous atmosphere therein, a tube of transparent, refractory material surrounding the electric discharge path between said electrodes and open-ended chambers for said electrodes, said tube being of quartz, said chambers having the same coefllcient of expansion as said container and being fused to said container atthe base of the stems thereof, the adjacent ends of said tube and said chambers being concentric and overlapping.

'3. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a tube of transparent, refrac- .tory material surrounding the electric discharge tainer, said chambers having the same coeflicient of expansion as said container, the adjacent ends of said tube and said chambers being concentric and overlapping, the stem parts of said container being in parallel planes.

4. An electric discharge device comprising a container, electrodes sealed therein, a gaseous atmosphere therein, a tube of transparent, refractory material surrounding the electric discharge path between said electrodes and open-ended chambers for said electrodes, said tube having a different coeflicient of expansion than said container, said chambers having the same coefllcient of expansion as said container and being supported by a spring member pressing against the inner wall of said container, the adiacent ends of said tube and said chamber being concentric and overlapping.

5. An electric discharge device comprising a container having a plurality of stems, electrodes sealed therein, a gaseous atmosphere therein, open-ended chambers for said electrodes and a tube of transparent material surrounding the discharge path between said electrodes, said tube having a different coefficient of expansion than said container, the adjacent ends of said tube and said chambers being concentric and overlapping.

KURT WIEGAND. 

